The invention concerns a freight loading system and a method for controlling a plurality of freight handling devices on a freight deck.
To transport air freight, the freight items to be transported, in particular containers or pallets which are preferably produced to specific standards, are attached inside the cargo hold by means of locking elements on the freight deck of the cargo hold. Such locking elements frequently form freight loading tracks between which the standard freight items can be positioned. To position the freight items at the locations provided for them, loading systems or freight loading systems are used which assist the ground staff in loading and unloading. The loading systems are intended to accelerate the loading and unloading process and frequently have a plurality of actuators and sensors and a control computer which is adapted to evaluate the signals received, where applicable to output signals and implement a suitable control strategy for the actuators. The loading systems used must be very easy to operate since ground staff often receive no training in relation to a specific freight loading system. Also both loading and unloading take place under high pressure of time, whereby incorrect operation can easily occur. Such incorrect operation must absolutely be prevented. A faulty freight loading system, either because of incorrect operation or because of natural wear, can lead to substantial costs since operation of wide-bodied aircraft is very costly. Every minute a wide-bodied aircraft spends on the ground costs the operator money. Furthermore, a faulty freight loading system or incorrect operation can lead for example to damage to the cargo hold. Repair of the cargo hold is very expensive.
To structure the loading and unloading process as efficiently as possible, the freight deck has ball mats which allow the freight items to be transported on the freight deck with minimum force. Furthermore freight handling devices (PDUs: power drive units) are provided which supply the force necessary for transport. The control computer controls these freight handling devices to allow preferably substantially automatic loading and unloading. Nonetheless, on loading and unloading of aircraft, ground staff are still essential since many loading processes are highly individual because of the different dimensions of the freight items, their projections etc. So modern freight loading systems have input devices which allow the ground staff to give control commands to the control computer.
DE 10 2008 052 468 A1 shows for example a freight loading system for an aircraft comprising a control computer and a plurality of freight handling devices in communicative connection with the control computer. The control computer operates the freight handling devices such that the freight items are positioned in a suitable manner on the freight deck of the aircraft. DE 10 2008 052 468 A1 furthermore describes a remote control which enables the user to move freely on the freight deck and give suitable control commands in the form of control signals. Handling of this remote control is relatively complex. A further freight loading system is known from EP 0 937 643.
Corresponding freight loading systems are also used in logistics centres. Such logistics centres are located for example at major transhipment airports which daily receive thousands of freight items and pass these on for further transport in a suitable manner. Also frequently freight decks are provided in corresponding logistics centres, which are equipped with corresponding rollers to convey the freight items with as little friction as possible. Here too, freight handling devices can be provided which communicate with a control computer to transport the freight items in a suitable manner on the freight deck. In fact similar requirements to those already described above apply to freight loading systems in logistics centres. In particular it is necessary to make their operation as simple as possible.
Starting from DE 10 2008 052 468 A1, an object of the present invention is to provide a freight loading system which can be operated simply and efficiently. Furthermore a corresponding method is provided for controlling a plurality of freight handling devices of a freight loading system.
In particular the object is achieved by a freight loading system comprising:
a freight deck with a plurality of freight handling devices;
a control unit which is in communicative connection with the freight handling devices for the transport of at least one freight item on the freight deck;
a remote control which is in communicative connection with the control unit for the output of control signals to the control unit.
An essential concept of the present invention is that the control unit is equipped with a position determination unit to determine a remote control position on the freight deck and/or the orientation of the remote control, wherein the control unit is adapted to select a quantity of freight handling devices and drive these as a function of the control signals received and the remote control position and/or orientation of the remote control.
The freight loading system according to the invention can be used both in aircraft and at any other location, in particular in logistics centres. A core concept of the invention is that the control unit knows the precise or approximate position and/or the precise or approximate orientation of the remote control, and interprets the control signals output by the remote control differently as a function of these parameters. As a result it is possible to design the remote control substantially more simply, since for example selection of the freight item to be transported on the freight deck can be made automatically. For example the control unit can assume that the freight item to be transported is always the one closest to the remote control.
It is even conceivable to allow the remote control to communicate with the control unit by hard-wired connection, but preferably a wireless communication is used. The remote control can be adapted to transmit the control signals at least partly wirelessly, in particular by means of light waves, to the control unit. To this extent it is possible for the user to move freely about the freight deck.
The position determination unit can be adapted to determine at least one freight item position of the at least one freight item on the freight deck, wherein the control unit is adapted to drive the freight handling devices as a function of the control signals received, the remote control position and/or the orientation of the remote control, and the position of the at least one freight item.
Insofar as the control unit knows both the position of the remote control and/or its orientation, and the position of the at least one freight item, these parameters can be taken into account in the interpretation of the control signals. It is for example easily possible to determine the freight item closest to the user, or the freight item which he is looking at directly. The control unit can be configured such that it assumes that the control signals output by means of the remote control always relate to the freight item which the user is looking at, that to which the remote control is pointing and/or that which is closest to the remote control.
The control device can be adapted to take into account the remote control position and/or the orientation of the remote control relative to the at least one freight item. It is however also possible to change the function method of the remote control depending on the relative position and/or orientation.
The remote control can comprise at least one first actuation device to which a “follow” control signal is allocated, wherein the control device is adapted, on reception of the “follow” control signal, to determine a transport direction in which the at least one freight item is to be transported in the direction towards the remote control position, and controls the handling device such that the at least one freight item is transported in the calculated transport direction.
The remote control can thus be used in the manner of an “electronic lead”, wherein actuation of the first actuation device leads to the output of control signals which cause the control device to move a selected freight item towards the user or towards the position of the remote control. To this extent the user can walk ahead of the freight item and, by actuating the first actuation device, cause a selected freight item to follow him. The actual control of the freight handling device and the selection of a suitable transport direction need therefore no longer be made by the user, since the control device knows the position of the freight item and the position of the remote control and possibly its orientation.
Consequently the remote control can comprise at least one second actuation device to which a “back” control signal is allocated, wherein the control device is adapted, on reception of the “back” control signal, to determine a transport direction in which the at least one freight item is moved in a direction away from the remote control position, and controls the handling devices such that the at least one freight item is transported in the calculated transport direction. Similarly the remote control can have thus a second actuation device, actuation of which leads to the output of control signals which cause the control unit to move a selected freight item away from the user or from the remote control. To this extent it would for example be conceivable for the user to walk behind the freight item and guide this ahead of him. Preferably this second transport mode is used to park the freight items for example in a space without danger to the user. Theoretically it is conceivable to provide one or more further actuation devices which allow rotation of the freight item. Here too theoretically the transport strategy implemented by the control device can depend on the position and/or orientation of the remote control relative to the freight item.
Furthermore it is possible, by detecting the position of the remote control, to implement various safety mechanisms which allow protection of the user and the equipment used. For example the control device can comprise a distance determination device to determine an actual distance between the freight item position and the remote control position, and be adapted to deactivate at least the selected number of freight handling devices if the actual distance is less than a predefined safety distance. Thus for example a freight item can be prevented from running over the user. Furthermore it is conceivable to use the teaching according to the invention on a freight deck in which a plurality of users are active with a plurality of remote controls. By taking into account the distance between the remote controls and the freight items, accidents can also be avoided in which a user is run over by a “foreign” freight item.
The control system can be adapted, using the remote control position and orientation of the remote control, to select from a plurality of freight items one which is to be transported according to the control signals. To this extent the teaching according to the invention simplifies the allocation of the control signals to a specific freight item to which they relate.
The freight loading system can comprise a plurality of receiver units for receiving the control signals and preferably arranged covering the surface of the freight deck, wherein the position determination device knows the positions of the receiver units and from the positions of the receiver units which receive a control signal output by the remote control, determines the remote control position. Theoretically it is possible to determine the position of the user of the remote control or of the remote control itself by means of additional devices (e.g. GPS or local position determination systems). Preferably however the position is determined with sufficient accuracy that the control signals are received only by one or by few receiver units from the plurality of receiver units. The positions of the receiver units which receive the control signals give a sufficiently precise conclusion on the positions of the remote control or the position of the user of the remote control. It is conceivable to reduce the transmission power of the remote control such that only very few, preferably only one receiver unit receives the control signals in a particular position. Theoretically the receiver units can also be adapted to allocate to the received control signal a direction from which this is received, so that firstly the position determination is more precise and secondly conclusions can be drawn on the orientation of the remote control. Theoretically it is furthermore possible to structure the transmitter of the remote control such that individual receiver units can be addressed. This is easily possible in particular if infrared signals are used. To this extent the user can direct the remote control at a specific receiver unit which for example is allocated to a specific freight item, and thus make a selection from the freight items.
In particular the object is achieved by a method for controlling a plurality of freight handling devices of a freight loading system, in particular of a freight loading system as already described, wherein the method comprises the following steps:
reception of a control signal from a remote control, in particular by means of an IR receiver device;
determination of at least one remote control position of the remote control;
determination of at least one freight item position of at least one freight item on a freight deck;
selection of a quantity of freight handling devices arranged on the freight deck;
determination of a transport direction for each freight handling device from the selected quantity as a function of the control signal received, the remote control and the freight item position;
driving of the freight handling devices in the respective transport direction.
According to the method therefore the remote control positions and where applicable the freight item position are taken into account in the interpretation of the control signal or signals received. By taking into account these parameters, both the operating comfort and the safety can be increased during control of the plurality of freight handling devices.
The selected quantity of freight handling devices can be dependent on the remote control position determined and/or the orientation of the remote control. It is also possible using the position data not only to influence the manner in which a specific freight item is transported in response to the reception of a specific control signal, but also the selection of the freight item to be transported can depend on these data.
Determination of the remote control position can comprise determination of a primary receiver unit from a plurality of receiver units arranged on or close to the freight deck, and determination of the position of the primary receiver unit on the freight deck, wherein the primary receiver unit is the receiver unit which receives the control signal from the remote control. Naturally it is conceivable for several receiver units to receive a particular control signal. In this case for example the primary receiver unit could be the receiver unit which receives the strongest control signal. With the method specified, the position of the remote control can easily be determined.
The method can comprise calculation of an actual distance between the freight item position and the remote control position, wherein the selected freight handling devices are driven only when the actual distance is greater than a predefined safety distance. To this extent safety mechanisms can be implemented to protect the user and the equipment.
The method can comprise calculation of at least one freight distance between a first freight item and a second freight item, wherein the selected freight handling devices are driven only when the calculated freight distance between the first and second freight items, between which the remote control is located according to the specific remote control position, is greater than a predefined safety distance.